1. Field of the Invention
This invention relates to roofing systems, and, more particularly, to reinforcing the attachment of the top coat of lightweight insulating concrete to an underlying lightweight concrete slurry coat and roof deck structure to provide greater resistance to wind uplift forces.
2. Discussion of the Related Art
Currently, lightweight insulating concrete is installed over metal, gypsum, tectum or concrete roof decks by applying a ½ inch to ¾ inch slurry coat of lightweight concrete into which a layer of EPS (expanded poly styrene) board insulation is placed. The EPS ridged board insulation has three inch diameter holes formed through its thickness in a spaced arrangement. The holes in the EPS board insulation allow the slurry coat of lightweight concrete to mate with a subsequently applied two inch top coat layer of lightweight insulating concrete. This attaches the top coat of lightweight concrete to the underlying slurry coat, with the EPS board insulation encapsulated therebetween. The slurry coat is poured directly on top of the metal, gypsum, tectum or concrete roof deck which, in some instances, results in a weak connection. Once the lightweight insulating concrete has cured over a 12 to 36 hour period, the roof membrane system is applied.
Despite the widespread use of lightweight insulating concrete, there is a significant drawback associated with the attachment of the lightweight concrete to the underlying roof deck structure. In high wind conditions, and particularly hurricane force winds, there is a need for reinforced attachment of the lightweight insulating concrete top coat to the metal, gypsum, tectum or concrete roof deck in order to prevent the lightweight concrete from losing its bond to the roof deck which, otherwise, may cause the roof system to fail.